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FXAK67 PAJK 262215
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
215 PM AKDT Wed Jun 26 2024

.SHORT TERM.../through Thursday night/...Weak upper level low
over the eastern gulf will weaken and slide towards Haida Gwaii
during the short term forecast. So leftover, light rain showers
drifting into the panhandle from Canada is still a possibility.
But the surface high pressure in the gulf would slow down that
westward advancement. So to say "confidence is low" on the rain
shower forecast would be an understatement. That being said, any
showers that do make it over the mountains would be light and
won`t last long.

The other struggle of the forecast is the high temps vs sky cover
forecast. Surface high over the gulf would, normally, give the
area clear skies. But the easterly wave in Canada has been
delivering a those clouds we`ve been seeing dotting the satellite
and webcams. So for now, went with partly to mostly sunny clear
skies beginning tonight and lasting into tomorrow night.

The high temperatures for Thursday will be like today, highly
dependent on cloud cover. Clearer skies would give warmer temps.
Extra cloud cover would limit how high temps warm. Went ahead and
didn`t change inherited forecast, so kept highs in the upper 60s
to 70s.

The exception is for those folks right along the coast, (Yakutat,
Elfin Cove, Pelican, Sitka, etc) where a marine layer cloud deck
is possible. If it does build up enough to slide along the coast,
that could keep temps for those areas in the upper 50s to low 60s.
But if the clouds don`t move in, high temps will end up being in
the upper 60s to near 70.

.LONG TERM...For the start of the long term, the possibility of
some easterly showers moving over the area. Winds should remain
light with the exception of near some of these showers which could
bring some localized gusty winds. This will continue before
models continue to show that a low will enter the southern gulf
which will bring an increased chance of precipitation for the
weekend and into next week. Overall, accumulations still look to
remain low but did up the forecast rain amounts for the area.
Deterministic and ensemble guidance continue to show a overall
weak system that looks to potentially persist headed into next
week which could aid in more easterly wave showers returning to
Southeast Alaska.

&&

.AVIATION...VFR prevailing at all airports in SE Alaska this
afternoon with a bit of a seabreeze setting up in the central and
northern Panhandle area where breaks of sun are more prevalent. We
have some thunderstorms being observed across northwestern British
Colombia and the southern Yukon Territory this afternoon, but this
activity has been weakening as it approaches the Alaska border.
Main forecast challenge for the next 24 hours is how much marine
layer will set up under a light wind regime. We did put in some
low clouds (IFR/MVFR) for a few sites in the early morning where
the pattern would typically indicate stratus development, but
nothing extensive. We expect VFR by early afternoon tomorrow
across SEAK.

&&

.MARINE...Due to quiet winds and surface high pressure over the
gulf, no big concerns for the marine zones in the short term
forecast. Wave heights of 3 to 5 feet in the gulf with inner
channel waves forecasted to be around 1 to 3 feet. Northern Lynn
could see the highest waves, around 3 feet, due to wind speeds
increasing to around 15 knots Thursday afternoon.

&&

.HYDROLOGY...Chilkat River remains above minor flood stage today
due to higher elevation snow melt. Temperatures are expected to
remain high over the next several days and are even expected to
increase as cloud cover diminishes. Flower Mountain Snotel site
shows around 7.6 inches of SWE still in the snowpack at 2500 feet
elevation so there is still a decent amount of snow to melt at
higher elevations of the Chilkat basin. As such the Chilkat River
it expected to remain above minor flood stage for the next few
days at least and the advisory may need to be extended if high
water persists.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...None.

&&

$$

SHORT TERM...GJS
LONG TERM....SF
AVIATION...JG
MARINE...GJS
HYDROLOGY...GJS

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